Tube-squaring attachment



Aug. 22, 1950 s. RYSZKOWSKI TUBE SQUARING ATTACHMENT Filed July 12, 1947 Patented Aug. 22, 1950 UNITED STATES PATENT OFFICE TUBvE sQUARiNG ATTACHMENT.

Stanley Ryszkowski, Chicago, 111;, assignor to WilliamF. Stahl, Kenilworth, Ill.

Applioationul'uly 12, 1947,.S8EialN0. 760,667

2:0laims. 1.

This invention relates to a tube-squaring attachment, a, tube-forming'apparatus, and to the process of rendering the walls or a polygonal'tube true and straight;

For many years, paper tubes have beenzformed by drawing dry and gummed' paper tape strips upon a rotating mandrel while advancing the .mandrel and'tamping the sides of. the tape against the'mandrel sides. Square tubes have thus been formed and tubes of other than polygonal shape in cross section have been produced. The most common formofftube is the square or rectangular tube: which. receives a metal cor-.e'to be used in the forming of electrical apparatus. The dinicultyr experienced is'with: the paper tube, the side walls-oi; which tend; to. bulge and thus prevent t'heinsertionz of. the metal core in. the assembly operation. To meet this problem, it has been the practice for many years to hand-treat the tubes so as to straighten the side walls and thussquare up-the' tube. The operation is tedious and highly expensive, but it has been understood during the years to be the only method available.

An object of the present invention is toprovide apparatus for the. automatic. squaring of the tube or straightening its walls. A further object is to provide a new means and process which: will automatically square a paper, resinoils, or plastic laminated tube while utilizing the A standard. machine which has been in use for many years. Yet another object is toprovide a=simple attachment structure which utilizes the rotating and advancing mechanism of standard tube-forming equipment for automatically straightening the sides of a polygonal tube, the mechanism being efiective even though the tube rotates with the mandrel. Other specific objects and advantages will appear as the specification proceeds.

The invention is illustrated, in a preferred embodiment, by the accompanying drawing, in which- Figure 1 is a perspective view of apparatus embodying my invention; Fig. 2, an enlarged vertical sectional view of the tube-squaring device; and Fig. 3, a perspective view of the die employed,

The tube-forming apparatus is well known in the art and need not be described in detail herein.

A full description is given in Patents No. 1,782,- 618 and No, 1,625,470. It will be suffioient for the purposes herein to describe the machine briefly as follows: T represents a table on which the tube-forming mechanism is supported. R

2 is the means for reciprocating the mandrel M. The. mandrel shown near its forward. end is of a square shape so as to form a relatively square tube thereon. S is the means for rotating the mandrel. Qisthe bearing for the mandrel. The advancing mechanism is operated by the motor. P.

Dry paper tape A is fed onto the mandrel from one side. thereof. and gummed tape B in several strips is fed onto the other side of. the mandrel, as shown in Fig. 1. A. device Kis provided for supplying moisture to the gummed' side ofthe tape if the tape is gummed,.or for. supplying glue to the bottom oi strips B if. they have not been pregummed. The tube formed by the drawing of the tape strips A and B thereon is passed through an ironing and gripping device I, whicl'lis of well-knownconstruction. From I; the completed paper tube I0 is advanced,v as shown more clearly inaFig. 1. The machine. is old and its operation readily understood, and the foregoing descriptionis believed to be sufiicient for the understanding thereof.

In combination with the foregoing machine, I' provide a standard l l secured to the table T and having, a relatively wide. aperture [2 therethrough. Against thestandard II is a fiber disk I13 which serves as a wear member to protect the standard during the. rotation. of the die [4.

The die 54-, as. shown more. clearly inFigs. 2 and'3', consists of four metal bars l5, each having alongitudinalslot I16. extending therethrough and each. having one end thereof. tappedto receive a bolt IT. The head of the bolt rests against the outer side of each bar I5, and the threaded portion extends through the slot and engages the tapped end of another bar. In this manner, the four bars are brought together to provide a square or rectangular perimetric frame. I prefer to bevel the inner edges of the die members, as indicated by the numeral l8. The slight incline or bevel leads the tube gradually into the more constricted portion of the die and is effective in producing a smooth and finished exterior wall.

If desired, the fiber disk l3 may be dispensed with, and the die itself may be permitted to bear against any fixed abutment. The disk, however, is valuable as a, wear member and in reducing friction and noise, etc. It will be understood that the disk I3 may be formed of any suitable material.

In the illustration given, the die M is formed in a particular manner which permits its ready adjustment, but it will be understood that fixed dies may be used and a large number of different structures utilized for the purposes herein set out.

3 Operation In the operation of the machine, the dry or ungummed tape A is fed onto the rotating mandrel M and the gummed tape B is fed thereon, forming a complete tube emerging from the structure I. At the same time, the tube is advanced by the mechanism R which reciprocates, rotating the tube during its forward stroke but leaving the tube without rotation during its backward stroke. Since the operation of the old machine is well understood, a further description thereof will not be given.

Completed tube I is passed through the die l4 and through the opening l2 of standard Ii. It will be noted that the die [4 rests freely upon the tube, being advanced On the mandrel, and rotates therewith. However, the die I4 is prevented from advancing with the tube by reason of the standard II and the annular disk 13.

The result, therefore, is that the die [4 remains in one position but rotates with the mandrel and shaft. At the same time, the advancing mechanism causes the tube to pass through the constricting or trueing walls of the die [4 and thus render the walls straight and true. Usually, an automatic cutting device severs the tube after it reaches a certain distance beyond the standard H, and the tube is then ready for use.

The tube after having passed through the die I4 is found to have true walls and to fit perfectly the metal core which is to be inserted snugly therein. The hand operations heretofore required for straightening the walls of the tube are obviated.

The die 14 is particularly useful in the present operation because it can be quickly adjusted to handle any type of tube being passed through the machine, whether the tube be square or rectangular and of different dimensions. Further, the outwardly-extending ends of the bars l provide a wider frame, thus distributing the thrust over a wider area of the disk [3. The structure is extremely simple, inexpensive, and highly efficient.

It will be observed that the mandrel M does not extend through the die but terminates well short of the die, as indicated in dotted lines in Fig. 1. I have found that when the die opening is smaller than the peripheral dimensions of the mandrel, a far better adhesion takes place and a more effective squaring of the tube is brought about. The tube, by reason of the paper density, humidity, glue and water content, gives varying results with respect to the bowing or arcing of the sides of the tube. By contracting and sometimes expanding the die, an accurate control of the shape of the side walls is obtained. Thus, irrespective of the varying factors which influence the shape of the side walls of the tube, I am able to correlate the size of the die with respect to the size of the mandrel, and thus to produce the product of the desired shape. Further, the use of a die having an opening smaller than the periphery of the mandrel, results in much better adhesion in the laminated structure.

The tube may be formed of paper strips, cellulose acetate, and any other desired resinous or plastic strip material.

While in the foregoing specification, I have set forth the improved apparatus in considerable detail for the purpose of illustrating one embodiment of the invention, it will be understood that such details of structure may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

1. A tube-forming die comprising four bars provided with transverse slots extending longitudinally thereof, each bar having a tapped end, and headed bolts extending through said slots and engaging said tapped ends to form a foursided die.

2. A tube-forming die comprising four bars provided with transverse slots extending longitudinally thereof, each bar having a tapped end, and headed bolts extending through said slots and engaging said tapped ends to form a four-sided die, said die having its inner forward edge portions cut away to provide a beveled wall leading inwardly and rearwardly to compress and shape a tube passing therethrough.

STANLEY RYSZKOWSKI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 480,017 Hobbs et a1. Aug. 2, 1892 1,037,246 I-Iarbeck et a1. Sept. 3, 1912 1,114,870 Ehrick Oct. 27, 1914 1,782,618 Jauch Nov. 25, 1930 2,343,096 Stahl Feb. 29, 1944 

